[1] If you want to firewall your real hosts, re-writing PASV->PORT means you can open just outgoing connections from the FTPD, instead of the usual opening of all anonymous ports (usually 49152-65535).[2] The lbnc sends "IDEN [ident]@ip.ip.ip.ip\r\n" to the FTPD immediately. The server should not reply with anything. Currently, I know only of my own "lundftpd" which supports this.

Source

CVS only, check out "ssl-lbnc".CVS details are contained elswhere on this siteHowever, if you really don't have CVS there is a semi-fresh version ssl-lbnc-0.1b28.tgz available.